OSHA Specifications for Accident Prevention Signs (1910.145) requires the use of safety signs to indicate and define specific hazards that, without identification, may lead to accidental injury to workers and/or the public or to property damage.

OSHA 1910.145 has specific guidelines as to the definition of what constitutes a danger sign and a caution sign. According to this regulation, "Caution signs shall be used only to warn against potential hazards or to caution against unsafe practices" (1910.145(c)(2)(i)). The regulation for danger signs indicates, "There shall be no variation in the type of design of signs posted to warn of specific dangers and radiation hazards" (1910.145(c)(1)(i)).

OSHA also regulates the safety of the actual sign design. Signs need to have rounded or blunt corners and cannot have sharp edges or projections. Red, black and white are the colors designated for danger signs. Caution signs have a yellow background, and the panel is black with yellow letters. Text used on the yellow background must be black. OSHA requires the wording of safety signs to indicate positive actions rather than negative, and to be concise and easy to read.

Biological hazard signs are used "to signify the actual or potential presence of a biohazard and to identify equipment, containers, rooms, materials, experimental animals, or combinations thereof, which contain, or are contaminated with, viable hazardous agents" (1910.145(e)(4)).

The table on the right is a guide to choosing the appropriate sign classification for your application that is in compliance with OSHA regulations.

If you are unsure about compliance regulations, which signs are needed for a particular application, or which materials will provide the most value in harsh environments, you may need recommendations and guidance. Choosing a reputable sign vendor that has people on staff familiar with regulatory requirements will make it easier to ensure the signs you purchase are in compliance and will provide long-term value.